CAREER: Balancing Local and Systemic Resilience in the Western Water Network

这项教师早期职业发展（Career）资助将模拟西部地区水系统的大部分组成部分，以帮助促进地方和区域层面的弹性供水和使用规划。水库、渡槽和水泵系统的建设改变了美国西部的水文景观。这些工程壮举通过在空间上（通过跨流域转移和分配基础设施）和在时间上（通过在潮湿时期储存水以备以后使用）移动水，促进了经济增长。因此，曾经独立的河流流域现在通过水转移和共享需求中心联网，这里称为西部水网。区域供水网络的建立带来了好处，因为水可以在流域之间流动以满足需求，用水户可以通过一系列供应减轻干旱的影响。然而，这种连通性也带来了新的风险。正如金融系统之间的联系可以减少局部冲击的风险，同时增加系统不稳定的风险一样，相互联系的供水系统在局部风险和系统性风险之间存在权衡。随着气候变化、需求变化以及未来几年对运营规则的重新谈判，这些权衡将会发生变化。该项目将使用一套模型来评估最近和当前规则结构下地方（如市或州一级）和系统（如流域范围）恢复力之间的权衡，并探索修改措施，以减少在可能的未来条件下失败的风险。在重新设计操作规则和基础设施时，对这些权衡的新认识将允许审慎地选择利益和风险。由于相互关联的河流流域并非美国西部独有，因此对西部水网研究的经验教训可能适用于全球。该项目解决了在理解网络水系统中地方和系统弹性之间的权衡以及基础设施和制度设计的作用方面的空白。由于供水系统经过高度优化，能够承受观察到的历史变化，但社会和气候变化正在推动全球许多供水系统超越这些历史条件，因此，这些权衡的新知识现在尤为重要。由于这些强大的系统往往脆弱到超出其先前经历的脆弱范围，我们现在需要为预计的变化准备好我们的基础设施和制度系统。具体而言，该项目将：1)开发区域流量的统计模型，该模型考虑了在历史和预测条件下评估区域水系统的空间和时间模式；2)建立并测试西部水网测试用例的模型，该模型将水系统建模与能够模拟日常操作和自适应变化的基于代理的模型相结合；3)评估该系统在古历史和预测的水流条件下的当前运行情况；4)评估近期和当前规则结构下的局部和系统弹性之间的权衡，并探索在合理的未来条件下减少脆弱性空间的修改。为了实现这项工作，团队将与涉众合作，从他们对系统的隐性知识中学习，并共享结果。认识到下一代工程师面临的基础设施挑战的多面性，该项目还将开发教育模块和技术，以指导学生在课堂内外的综合应用。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This Faculty Early Career Development (CAREER) grant will model a large component of the western regional water system to help facilitate planning for resilient water supply and usage at both local and regional levels. The construction of reservoirs, aqueducts, and pump systems has transformed the hydrological landscape of the American west. These feats of engineering have facilitated growth by moving water in space (via interbasin transfers and distribution infrastructure) and in time (by storing water during wet periods for later use). Consequentially, once separate river basins are now networked via water transfers and shared demand centers, here termed the Western Water Network. The creation of a regional water supply network generated benefits as water can be moved across basins to meet demands and water users can mitigate drought impacts with a portfolio of supplies. However, this connectivity also introduces new risks. Just as links in financial systems can reduce the risks of local shocks while raising the risk the system instability, interconnected water supply systems have tradeoffs between local and systemic risks. These tradeoffs are primed to shift as climatic change, demand shifts, and a renegotiation of operating rules play out in the coming years. This project will use a set of models to assess the tradeoffs between local (e.g. municipal or state level) and systemic (e.g. basin wide) resilience under recent and current rule structures and explore modifications to reduce the risk of failure under plausible future conditions. New knowledge of these tradeoffs will allow the deliberate choice of benefits and risks when re-designing operating rules and infrastructure. As interconnected river basins are not unique to the America West, lessons from study of the Western Water Network may be applicable globally. This project addresses a gap in understanding the tradeoffs between local and system resilience in networked water systems, and the role of infrastructure and institutional design. New knowledge of these tradeoffs is particularly relevant now as water supply systems are highly optimized to tolerate observed historic variability but both social and climatic changes are pushing many water supply systems globally beyond these historic conditions. As such robust systems are often fragile beyond their range of previously experienced vulnerability, we need to prepare our infrastructure and institutional systems now for projected changes. Specifically, this project will: 1) develop statistical models of regional streamflow that account for both the spatial and temporal patterns critical to evaluating regional water systems under historic and projected conditions; 2) build and test a model of the test case Western Water Network that merges water systems modeling with an agent-based model capable of simulating routine operations and adaptive changes; 3) evaluate the system as currently operated under paleo-historic and projected streamflow conditions; and 4) assess the tradeoffs between local and systemic resilience under recent and current rule structures and explore modifications to reduce the fragility space under plausible future conditions. To implement this work, the team will collaborate with stakeholders to both learn from their tacit knowledge of the system and share results. In recognition of the multifaceted nature of infrastructure challenges facing the next generation on engineers, this project will also develop educational modules and techniques for guiding students through synthesis that are applicable within and outside the classroom.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.